Wash the tomatoes in cold water. Core and quarter the tomatoes, placing into the enamel pot.
Once the pot is full, with about 4 or more inches from the top, place on the stove and begin to cook, stirring to keep from burning on the bottom. (you have to be able to stir this!)
While it is cooking, get the food mill ready to process the crushed tomatoes.
Once the tomatoes are soft, you can remove from heat and begin to run through the food mill.
The electric food mill attachment is great for large batches like this. Run the food mill on low speed to keep it from splattering everything. And put towels down before you start! If you have a hand food mill, don't go crazy and make sure the mill and pot are secure and not moving all over the counter.
While working on the tomatoes, have the water bath canner on the stove heating. Fill a little less than 3/4 full (less if processing quarts).
Once all the juice has been extracted, wash out the enamel pan and pour the juice back into it.
Put the tomato juice on the heat and heat the juice to 190F for 5 minutes.
Remove from the heat and begin placing the tomato juice into the jars.
Add 1 tablespoon bottled lemon juice in pints, 2 tablespoons for quarts.
Clean the rim of the jar and place the seal on top. Cover with a band and hand tighten.
Process the jars in the water bath canner 35 minutes pints, 40 minutes quarts.
Allow to sit for 5 minutes before removing.
Once removed, place towels around the jars, to slow the cooling process.